A new method of introducing single-molecule-quality fluorophores into live bacterial cells for superresolution imaging studies has been developed by researchers in the US.
Superresolution imaging can image structures with a spatial resolution 5 to 10 times smaller than the diffraction limit of about 200nm for visible wavelengths. In contrast to previous ideas, the team allows a permeable dye molecule (the substrate) to enter the cell in a fluorescently deactivated state.
Subsequent photoactivation by reaction with the enzyme nitroreductase produces fluorescent products whose concentration is controlled by the level of substrate uptake. Importantly, fluorophores can enter living cells fairly easily because they are neutral, and they emit at long wavelengths to avoid autofluorescence.
Read this ‘HOT’ Chemical Science article today:
Enzymatic Activation of Nitro-Aryl Fluorogens in Live Bacterial Cells for Enzymatic Turnover-Activated Localization Microscopy
Marissa K. Lee, Jarrod Williams, Robert Twieg, Jianghong Rao and W.E. Moerner
Chem. Sci., 2012, DOI: 10.1039/C2SC21074F